I am baffled at sighting in my rifle

[z.chance]

My M&P Sport 2 is accurate as all get out, but I am completely at a loss with what is happening here...I am using a Redfield Revolution 2x7x32 scope and a Burris PEPR QD mount. At 30 yards I am making a 1/2" group (roughly, all holes touching) dead center of the bull. At 120 yards (approx) I am shooting a 1" group but it is 8" high. Left and right and still perfect, but what would cause an 8" high shot...? The group is perfect, and like I said, left and right are dead on. What in the world is going on? Anyone?

Thats how it works. You have a 30 yard zero, so it will shoot high at 120. If you zero at 120 it will shoot low at 30

 

[Kahrnut]

You'll shoot your foot off.

 

[gun guy17]

Your a Christian using an evil rifle for starters.

Ouch

 

[MRH]

If you zero at 100 yards using 5.56. Inside of that range the bullet impact is ALWAYS going to be below your point of aim, unless you hold over. Beyond 100 yards (or so close it won't matter much) your point of impact is ALWAYS going to be below your point of aim, unless you hold over.

Zero you rifle at what ever distance best fits your needs, taking into account optical offset and round choice. But you are always going to be holding over inside of your zero point, and eventually holding over at some distance, depending on the range of your initial zero.

A lot of people zero at 50 yards because the point of impact = point of aim at 50 yards and about 230 yards (assuming 55 grain 5.56 and a 16 inch barrel). In between 50 and 230 yards the max rise of the bullet above the point of aim is about 2 inches (assuming an optical offset of 2.25 inches, the standard height of an A2 front sight post above the center line of the barrel bore) . So from 50 to 230, put it where you want it to hit and be done with it. Inside of 50, same same until you get within 10 yards or so then hold over up to the max height of your optical offset at close range.

I am a 100 yard zero man myself. Hold over at extreme close range. Hold true out to 100 yards. Hold over beyond 100 yards.

I sight my rifles in at 100 too because that's about the range I normally shoot. Sometimes closer, sometimes farther, but 100 yards is about where I will be shooting.

I've sighted rifles all my life and have never had an 8" difference between 30-120 yards, but normally I sight around 100 and my closer shots are only a bit high...Like maybe 1"...

I appreciate all of the feedback. I learned something new today, and I know the rifle is very accurate.

 

[MRH]

View attachment 1555557

Looks like everything is working pretty much like it should if you zero' d at 30 yds.

Thanks. The M-193 is what I am using. This chart tells me what I need to know, and simply.

 

[Old_School]

Thanks. The M-193 is what I am using. This chart tells me what I need to know, and simply.

That's why I like a 50 yd zero on an AR. Never more than 2" above or below my point of aim from point blank to about 250 yds.

Sent from my XT1635-01 using Tapatalk

 

[MRH]

That's why I like a 50 yd zero on an AR. Never more than 2" above or below my point of aim from point blank to about 250 yds.

Sent from my XT1635-01 using Tapatalk

Exactly the point I was looking at because 250 is about as far as I will ever shoot this rifle.

 

[Porter Rockwell]

Lots of good info in this thread!

 

[Speed6]

Agreed, great info. I like to zero at 50 yards as well.

 

[Burdy]